急需一个英文介绍任何交通工具的文章不用太长,

急需一个英文介绍任何交通工具的文章不用太长,
急需一个英文介绍任何交通工具的文章不用太长,

急需一个英文介绍任何交通工具的文章不用太长,
Road transportation.Road infrastructures are large consumers of space with the lowest level of physical constraints among transportation modes.However,environmental constrains are significant in road construction.Road transportation has an average operational flexibility as vehicles can serve several purposes but are rarely able to move outside roads.Road transport systems have high maintenance costs,both for the vehicles and infrastructures.They are mainly linked to light industries where rapid movements of freight in small batches are the norm.
Rail transportation.Railways are composed of a traced path on which are bound vehicles.They have an average level of physical constrains linked to the types of locomotives and affected by the gradient.Heavy industries are traditionally linked with rail transport systems,although containerization has improved the flexibility of rail transportation by linking it with road and maritime modes.Rail is by far the land transportation mode offering the highest capacity with 23,000 tons fully loaded coal train being the heaviest load ever carried.
Maritime transportation.Because of the physical properties of water conferring buoyancy and limited friction,maritime transportation is the most effective mode to move large quantities of cargo.Main maritime routes are composed of oceans,coasts,seas,lakes,rivers and channels.However,maritime circulation takes place on specific parts of the maritime space,particularly over the North Atlantic and the North Pacific.The construction of channels,locks and dredging are attempts to facilitate maritime circulation by reducing discontinuity.Comprehensive inland waterway systems include Western Europe,the Volga / Don system,St.Lawrence / Great Lakes system,the Mississippi and its tributaries,the Amazon,the Panama / Paraguay and the interior of China.Maritime transportation has high terminal costs,since port infrastructures are among the most expensive to build,maintain and improve.High inventory costs also characterize maritime transportation.More than any other mode,maritime transportation is linked to heavy industries,such as steel and petrochemical facilities adjacent to port sites.
Air transportation.Air routes are practically unlimited,but they are denser over the North Atlantic,inside North America and Europe and over the North Pacific.Air transport constraints are multidimensional and include the site (a commercial plane needs about 3,300 meters of track for landing and take off),the climate,fog and aerial currents.Air activities are linked to the tertiary and quaternary sectors,notably finance and tourism that require movements of people.More recently,air transportation has been accommodating growing quantities of high value freight and is playing a growing role in global logistics.
Pipelines.Pipeline routes are practically unlimited.The longest gas pipeline links Alberta to Sarnia (Canada),which is 2,911 km in length.The longest oil pipeline is the Transiberian,extending over 9,344 km to Western Europe from the Russian arctic oilfields in eastern Siberia.Physical constraints are low and include the landscape and pergelisol in arctic / subarctic environments.Pipeline construction costs vary according to the diameter and increase proportionally with the distance and with the viscosity of fluids (from gas to oil).The Trans Alaskan pipeline,which is 1,300 km long,was built under difficult conditions and has to be above the ground for most of its path.Pipeline terminals are very important since they correspond to refineries and harbors.
Telecommunications.Telecommunication routes are practically unlimited with very low constraints,which may include the physiography and oceanic masses that may impair the setting of cables.They provide for the instantaneous movement of information (speed of light).Wave transmissions,because of their limited coverage,often require substations,such as for cellular phone networks.Satellites are often using a geostationary orbit which is getting crowded.High network costs and low distribution costs characterize many telecommunication networks,which are linked to the tertiary and quaternary sectors (stock markets,business to business information networks,etc).Telecommunications limit the requirement for personal movements in some economic sectors.

Telecommunications. Telecommunication routes are practically unlimited with very low constraints, which may include the physiography and oceanic masses that may impair the setting of cables. They prov...

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Telecommunications. Telecommunication routes are practically unlimited with very low constraints, which may include the physiography and oceanic masses that may impair the setting of cables. They provide for the instantaneous movement of information (speed of light). Wave transmissions, because of their limited coverage, often require substations, such as for cellular phone networks. Satellites are often using a geostationary orbit which is getting crowded. High network costs and low distribution costs characterize many telecommunication networks, which are linked to the tertiary and quaternary sectors (stock markets, business to business information networks, etc). Telecommunications limit the requirement for personal movements in some economic sectors.

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Transportation in ancient China was on poor condition. People traveled mainly on foot. It took several months for a candidate who expected to take the imperial examination to be a government official ...

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Transportation in ancient China was on poor condition. People traveled mainly on foot. It took several months for a candidate who expected to take the imperial examination to be a government official to go from home to the capital on foot. People also rode horses when traveling from town to town. For short-distance trips, man-carried sedans and carriages or oxcart were also used. Needless to say, all these means of transportation are in very low speed.

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